Table Selection

Deck Penetration

The percentage of cards dealt before the shuffle. One of the most important factors when choosing a table to count at.

📏 Penetration Formula

Penetration = Cards Dealt ÷ Total Cards

Example: 4 decks dealt from 6-deck shoe = 208 ÷ 312 = 67% penetration

A 6-deck shoe where 4 decks are dealt before shuffle = 67% penetration. This is the key number counters look for when choosing a table.

Why Penetration Matters for Counters

Count only gets meaningful late in the shoe. The running count starts at 0 (or KO starting value) and only reaches high values after many cards have been seen. At 40% penetration, you barely scratch the surface of what the count can tell you.

True count reliability. True Count = RC ÷ Decks Remaining. With fewer cards dealt, there are more decks remaining, which dilutes the true count even when the running count is high. Deep penetration amplifies every RC unit.

More betting opportunities. Deep penetration means more hands where TC is above your betting threshold. More high-count hands = more money made per shoe.

Penetration at a Glance

40%Count barely moves — mostly staying near 0
50%Marginal edge — barely worth counting
60%Standard — good game, solid edge
75%+Excellent — deep penetration is where money is made

The Casino vs. Counter Battle

Casinos know that penetration is the counter's best friend. Their primary countermeasure is to cut off more cards from the shoe — reducing penetration from 75% to 50% effectively halves a counter's edge. If you're being watched, the first sign is usually the cut card moving toward the front.

🚩 Warning Signs at the Table

  • • Cut card placed more than 2 decks from the back
  • • Mid-shoe shuffle after a big bet
  • • Cut card kept in the top half of the shoe
  • • Penetration consistently below 60%

Typical Penetration by Game Type

Single Deck

Best conditions — but rare and often countermeasured

70–80%

Double Deck

Good opportunities if dealt from hand

60–75%

6-Deck Shoe

Varies widely — always check before sitting

65–80%

8-Deck Shoe

Most common online; target 70%+ tables

65–75%

Estimating Penetration at the Table

Look at the discard tray and the remaining cards in the shoe. The cut card position tells you the casino's target.

Cut card 1 deck from back (6d shoe)~83%

Excellent ✅

Cut card 1.5 decks from back~75%

Very Good ✅

Cut card 2 decks from back~67%

Good ✅

Cut card 3 decks from back~50%

Marginal ⚠️

Cut card in top half of shoe<50%

Walk away ❌

📏 Minimum Viable Penetration

For 6-deck and 8-deck games: 50% minimum, 65%+ preferred. Below 50%, the count rarely reaches actionable true counts — the edge is too diluted to be worth the heat risk. For single and double deck, 60% minimum.

Bet Spread by Penetration (Hi-Lo, 6-deck)

With shallower penetration, tighten your spread to reduce heat while your edge is smaller. With deep penetration, a wider spread captures more value.

40%Shallow — count rarely moves
Spread 1:4

TC+2=2u, TC+3=3u, TC+4+=4u

Max cards (6d): 125 cards

50%Marginal — edge exists but diluted
Spread 1:6

TC+1=1u, TC+2=2u, TC+3=4u, TC+4+=6u

Max cards (6d): 156 cards

60%Standard — solid for most situations
Spread 1:8

TC+1=1u, TC+2=3u, TC+3=5u, TC+4+=8u

Max cards (6d): 187 cards

75%Deep — high TC values reachable
Spread 1:12

TC+1=1u, TC+2=4u, TC+3=8u, TC+4+=12u

Max cards (6d): 234 cards

KO note: Shallow penetration hurts KO more than Hi-Lo because KO's pivot is an absolute RC value. At 40% penetration the KO pivot may never be reached — consider Hi-Lo for those conditions.

Practice with Penetration →True Count →